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2019-07-02treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner1-6/+1
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> (cherry picked from commit 2874c5fd284268364ece81a7bd936f3c8168e567) Signed-off-by: Joel Stanley <joel@jms.id.au>
2019-06-22KVM: PPC: Book3S HV: Don't take kvm->lock around kvm_for_each_vcpuPaul Mackerras1-8/+1
[ Upstream commit 5a3f49364c3ffa1107bd88f8292406e98c5d206c ] Currently the HV KVM code takes the kvm->lock around calls to kvm_for_each_vcpu() and kvm_get_vcpu_by_id() (which can call kvm_for_each_vcpu() internally). However, that leads to a lock order inversion problem, because these are called in contexts where the vcpu mutex is held, but the vcpu mutexes nest within kvm->lock according to Documentation/virtual/kvm/locking.txt. Hence there is a possibility of deadlock. To fix this, we simply don't take the kvm->lock mutex around these calls. This is safe because the implementations of kvm_for_each_vcpu() and kvm_get_vcpu_by_id() have been designed to be able to be called locklessly. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Reviewed-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-06-22KVM: PPC: Book3S: Use new mutex to synchronize access to rtas token listPaul Mackerras2-8/+7
[ Upstream commit 1659e27d2bc1ef47b6d031abe01b467f18cb72d9 ] Currently the Book 3S KVM code uses kvm->lock to synchronize access to the kvm->arch.rtas_tokens list. Because this list is scanned inside kvmppc_rtas_hcall(), which is called with the vcpu mutex held, taking kvm->lock cause a lock inversion problem, which could lead to a deadlock. To fix this, we add a new mutex, kvm->arch.rtas_token_lock, which nests inside the vcpu mutexes, and use that instead of kvm->lock when accessing the rtas token list. This removes the lockdep_assert_held() in kvmppc_rtas_tokens_free(). At this point we don't hold the new mutex, but that is OK because kvmppc_rtas_tokens_free() is only called when the whole VM is being destroyed, and at that point nothing can be looking up a token in the list. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-06-22KVM: PPC: Book3S HV: Use new mutex to synchronize MMU setupPaul Mackerras2-26/+41
[ Upstream commit 0d4ee88d92884c661fcafd5576da243aa943dc24 ] Currently the HV KVM code uses kvm->lock in conjunction with a flag, kvm->arch.mmu_ready, to synchronize MMU setup and hold off vcpu execution until the MMU-related data structures are ready. However, this means that kvm->lock is being taken inside vcpu->mutex, which is contrary to Documentation/virtual/kvm/locking.txt and results in lockdep warnings. To fix this, we add a new mutex, kvm->arch.mmu_setup_lock, which nests inside the vcpu mutexes, and is taken in the places where kvm->lock was taken that are related to MMU setup. Additionally we take the new mutex in the vcpu creation code at the point where we are creating a new vcore, in order to provide mutual exclusion with kvmppc_update_lpcr() and ensure that an update to kvm->arch.lpcr doesn't get missed, which could otherwise lead to a stale vcore->lpcr value. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-06-09KVM: s390: Do not report unusabled IDs via KVM_CAP_MAX_VCPU_IDThomas Huth1-0/+3
commit a86cb413f4bf273a9d341a3ab2c2ca44e12eb317 upstream. KVM_CAP_MAX_VCPU_ID is currently always reporting KVM_MAX_VCPU_ID on all architectures. However, on s390x, the amount of usable CPUs is determined during runtime - it is depending on the features of the machine the code is running on. Since we are using the vcpu_id as an index into the SCA structures that are defined by the hardware (see e.g. the sca_add_vcpu() function), it is not only the amount of CPUs that is limited by the hard- ware, but also the range of IDs that we can use. Thus KVM_CAP_MAX_VCPU_ID must be determined during runtime on s390x, too. So the handling of KVM_CAP_MAX_VCPU_ID has to be moved from the common code into the architecture specific code, and on s390x we have to return the same value here as for KVM_CAP_MAX_VCPUS. This problem has been discovered with the kvm_create_max_vcpus selftest. With this change applied, the selftest now passes on s390x, too. Reviewed-by: Andrew Jones <drjones@redhat.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Thomas Huth <thuth@redhat.com> Message-Id: <20190523164309.13345-9-thuth@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-09KVM: PPC: Book3S HV: Restore SPRG3 in kvmhv_p9_guest_entry()Suraj Jitindar Singh1-0/+1
commit d724c9e54939a597592de3659541da11fc7aa112 upstream. The sprgs are a set of 4 general purpose sprs provided for software use. SPRG3 is special in that it can also be read from userspace. Thus it is used on linux to store the cpu and numa id of the process to speed up syscall access to this information. This register is overwritten with the guest value on kvm guest entry, and so needs to be restored on exit again. Thus restore the value on the guest exit path in kvmhv_p9_guest_entry(). Cc: stable@vger.kernel.org # v4.20+ Fixes: 95a6432ce9038 ("KVM: PPC: Book3S HV: Streamlined guest entry/exit path on P9 for radix guests") Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-09KVM: PPC: Book3S HV: Fix lockdep warning when entering guest on POWER9Paul Mackerras1-2/+5
commit 1b28d5531e446a87bbefa5ced191c4cbd316576c upstream. Commit 3309bec85e60 ("KVM: PPC: Book3S HV: Fix lockdep warning when entering the guest") moved calls to trace_hardirqs_{on,off} in the entry path used for HPT guests. Similar code exists in the new streamlined entry path used for radix guests on POWER9. This makes the same change there, so as to avoid lockdep warnings such as this: [ 228.686461] DEBUG_LOCKS_WARN_ON(current->hardirqs_enabled) [ 228.686480] WARNING: CPU: 116 PID: 3803 at ../kernel/locking/lockdep.c:4219 check_flags.part.23+0x21c/0x270 [ 228.686544] Modules linked in: vhost_net vhost xt_CHECKSUM iptable_mangle xt_MASQUERADE iptable_nat nf_nat +xt_conntrack nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ipt_REJECT nf_reject_ipv4 tun bridge stp llc ebtable_filter +ebtables ip6table_filter ip6_tables iptable_filter fuse kvm_hv kvm at24 ipmi_powernv regmap_i2c ipmi_devintf +uio_pdrv_genirq ofpart ipmi_msghandler uio powernv_flash mtd ibmpowernv opal_prd ip_tables ext4 mbcache jbd2 btrfs +zstd_decompress zstd_compress raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx libcrc32c xor +raid6_pq raid1 raid0 ses sd_mod enclosure scsi_transport_sas ast i2c_opal i2c_algo_bit drm_kms_helper syscopyarea +sysfillrect sysimgblt fb_sys_fops ttm drm i40e e1000e cxl aacraid tg3 drm_panel_orientation_quirks i2c_core [ 228.686859] CPU: 116 PID: 3803 Comm: qemu-system-ppc Kdump: loaded Not tainted 5.2.0-rc1-xive+ #42 [ 228.686911] NIP: c0000000001b394c LR: c0000000001b3948 CTR: c000000000bfad20 [ 228.686963] REGS: c000200cdb50f570 TRAP: 0700 Not tainted (5.2.0-rc1-xive+) [ 228.687001] MSR: 9000000002823033 <SF,HV,VEC,VSX,FP,ME,IR,DR,RI,LE> CR: 48222222 XER: 20040000 [ 228.687060] CFAR: c000000000116db0 IRQMASK: 1 [ 228.687060] GPR00: c0000000001b3948 c000200cdb50f800 c0000000015e7600 000000000000002e [ 228.687060] GPR04: 0000000000000001 c0000000001c71a0 000000006e655f73 72727563284e4f5f [ 228.687060] GPR08: 0000200e60680000 0000000000000000 c000200cdb486180 0000000000000000 [ 228.687060] GPR12: 0000000000002000 c000200fff61a680 0000000000000000 00007fffb75c0000 [ 228.687060] GPR16: 0000000000000000 0000000000000000 c0000000017d6900 c000000001124900 [ 228.687060] GPR20: 0000000000000074 c008000006916f68 0000000000000074 0000000000000074 [ 228.687060] GPR24: ffffffffffffffff ffffffffffffffff 0000000000000003 c000200d4b600000 [ 228.687060] GPR28: c000000001627e58 c000000001489908 c000000001627e58 c000000002304de0 [ 228.687377] NIP [c0000000001b394c] check_flags.part.23+0x21c/0x270 [ 228.687415] LR [c0000000001b3948] check_flags.part.23+0x218/0x270 [ 228.687466] Call Trace: [ 228.687488] [c000200cdb50f800] [c0000000001b3948] check_flags.part.23+0x218/0x270 (unreliable) [ 228.687542] [c000200cdb50f870] [c0000000001b6548] lock_is_held_type+0x188/0x1c0 [ 228.687595] [c000200cdb50f8d0] [c0000000001d939c] rcu_read_lock_sched_held+0xdc/0x100 [ 228.687646] [c000200cdb50f900] [c0000000001dd704] rcu_note_context_switch+0x304/0x340 [ 228.687701] [c000200cdb50f940] [c0080000068fcc58] kvmhv_run_single_vcpu+0xdb0/0x1120 [kvm_hv] [ 228.687756] [c000200cdb50fa20] [c0080000068fd5b0] kvmppc_vcpu_run_hv+0x5e8/0xe40 [kvm_hv] [ 228.687816] [c000200cdb50faf0] [c0080000071797dc] kvmppc_vcpu_run+0x34/0x48 [kvm] [ 228.687863] [c000200cdb50fb10] [c0080000071755dc] kvm_arch_vcpu_ioctl_run+0x244/0x420 [kvm] [ 228.687916] [c000200cdb50fba0] [c008000007165ccc] kvm_vcpu_ioctl+0x424/0x838 [kvm] [ 228.687957] [c000200cdb50fd10] [c000000000433a24] do_vfs_ioctl+0xd4/0xcd0 [ 228.687995] [c000200cdb50fdb0] [c000000000434724] ksys_ioctl+0x104/0x120 [ 228.688033] [c000200cdb50fe00] [c000000000434768] sys_ioctl+0x28/0x80 [ 228.688072] [c000200cdb50fe20] [c00000000000b888] system_call+0x5c/0x70 [ 228.688109] Instruction dump: [ 228.688142] 4bf6342d 60000000 0fe00000 e8010080 7c0803a6 4bfffe60 3c82ff87 3c62ff87 [ 228.688196] 388472d0 3863d738 4bf63405 60000000 <0fe00000> 4bffff4c 3c82ff87 3c62ff87 [ 228.688251] irq event stamp: 205 [ 228.688287] hardirqs last enabled at (205): [<c0080000068fc1b4>] kvmhv_run_single_vcpu+0x30c/0x1120 [kvm_hv] [ 228.688344] hardirqs last disabled at (204): [<c0080000068fbff0>] kvmhv_run_single_vcpu+0x148/0x1120 [kvm_hv] [ 228.688412] softirqs last enabled at (180): [<c000000000c0b2ac>] __do_softirq+0x4ac/0x5d4 [ 228.688464] softirqs last disabled at (169): [<c000000000122aa8>] irq_exit+0x1f8/0x210 [ 228.688513] ---[ end trace eb16f6260022a812 ]--- [ 228.688548] possible reason: unannotated irqs-off. [ 228.688571] irq event stamp: 205 [ 228.688607] hardirqs last enabled at (205): [<c0080000068fc1b4>] kvmhv_run_single_vcpu+0x30c/0x1120 [kvm_hv] [ 228.688664] hardirqs last disabled at (204): [<c0080000068fbff0>] kvmhv_run_single_vcpu+0x148/0x1120 [kvm_hv] [ 228.688719] softirqs last enabled at (180): [<c000000000c0b2ac>] __do_softirq+0x4ac/0x5d4 [ 228.688758] softirqs last disabled at (169): [<c000000000122aa8>] irq_exit+0x1f8/0x210 Cc: stable@vger.kernel.org # v4.20+ Fixes: 95a6432ce903 ("KVM: PPC: Book3S HV: Streamlined guest entry/exit path on P9 for radix guests") Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Reviewed-by: Cédric Le Goater <clg@kaod.org> Tested-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-09KVM: PPC: Book3S HV: XIVE: Do not clear IRQ data of passthrough interruptsCédric Le Goater1-2/+2
commit ef9740204051d0e00f5402fe96cf3a43ddd2bbbf upstream. The passthrough interrupts are defined at the host level and their IRQ data should not be cleared unless specifically deconfigured (shutdown) by the host. They differ from the IPI interrupts which are allocated by the XIVE KVM device and reserved to the guest usage only. This fixes a host crash when destroying a VM in which a PCI adapter was passed-through. In this case, the interrupt is cleared and freed by the KVM device and then shutdown by vfio at the host level. [ 1007.360265] BUG: Kernel NULL pointer dereference at 0x00000d00 [ 1007.360285] Faulting instruction address: 0xc00000000009da34 [ 1007.360296] Oops: Kernel access of bad area, sig: 7 [#1] [ 1007.360303] LE PAGE_SIZE=64K MMU=Radix MMU=Hash SMP NR_CPUS=2048 NUMA PowerNV [ 1007.360314] Modules linked in: vhost_net vhost iptable_mangle ipt_MASQUERADE iptable_nat nf_nat xt_conntrack nf_conntrack nf_defrag_ipv4 ipt_REJECT nf_reject_ipv4 tun bridge stp llc kvm_hv kvm xt_tcpudp iptable_filter squashfs fuse binfmt_misc vmx_crypto ib_iser rdma_cm iw_cm ib_cm libiscsi scsi_transport_iscsi nfsd ip_tables x_tables autofs4 btrfs zstd_decompress zstd_compress lzo_compress raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq multipath mlx5_ib ib_uverbs ib_core crc32c_vpmsum mlx5_core [ 1007.360425] CPU: 9 PID: 15576 Comm: CPU 18/KVM Kdump: loaded Not tainted 5.1.0-gad7e7d0ef #4 [ 1007.360454] NIP: c00000000009da34 LR: c00000000009e50c CTR: c00000000009e5d0 [ 1007.360482] REGS: c000007f24ccf330 TRAP: 0300 Not tainted (5.1.0-gad7e7d0ef) [ 1007.360500] MSR: 900000000280b033 <SF,HV,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 24002484 XER: 00000000 [ 1007.360532] CFAR: c00000000009da10 DAR: 0000000000000d00 DSISR: 00080000 IRQMASK: 1 [ 1007.360532] GPR00: c00000000009e62c c000007f24ccf5c0 c000000001510600 c000007fe7f947c0 [ 1007.360532] GPR04: 0000000000000d00 0000000000000000 0000000000000000 c000005eff02d200 [ 1007.360532] GPR08: 0000000000400000 0000000000000000 0000000000000000 fffffffffffffffd [ 1007.360532] GPR12: c00000000009e5d0 c000007fffff7b00 0000000000000031 000000012c345718 [ 1007.360532] GPR16: 0000000000000000 0000000000000008 0000000000418004 0000000000040100 [ 1007.360532] GPR20: 0000000000000000 0000000008430000 00000000003c0000 0000000000000027 [ 1007.360532] GPR24: 00000000000000ff 0000000000000000 00000000000000ff c000007faa90d98c [ 1007.360532] GPR28: c000007faa90da40 00000000000fe040 ffffffffffffffff c000007fe7f947c0 [ 1007.360689] NIP [c00000000009da34] xive_esb_read+0x34/0x120 [ 1007.360706] LR [c00000000009e50c] xive_do_source_set_mask.part.0+0x2c/0x50 [ 1007.360732] Call Trace: [ 1007.360738] [c000007f24ccf5c0] [c000000000a6383c] snooze_loop+0x15c/0x270 (unreliable) [ 1007.360775] [c000007f24ccf5f0] [c00000000009e62c] xive_irq_shutdown+0x5c/0xe0 [ 1007.360795] [c000007f24ccf630] [c00000000019e4a0] irq_shutdown+0x60/0xe0 [ 1007.360813] [c000007f24ccf660] [c000000000198c44] __free_irq+0x3a4/0x420 [ 1007.360831] [c000007f24ccf700] [c000000000198dc8] free_irq+0x78/0xe0 [ 1007.360849] [c000007f24ccf730] [c00000000096c5a8] vfio_msi_set_vector_signal+0xa8/0x350 [ 1007.360878] [c000007f24ccf7f0] [c00000000096c938] vfio_msi_set_block+0xe8/0x1e0 [ 1007.360899] [c000007f24ccf850] [c00000000096cae0] vfio_msi_disable+0xb0/0x110 [ 1007.360912] [c000007f24ccf8a0] [c00000000096cd04] vfio_pci_set_msi_trigger+0x1c4/0x3d0 [ 1007.360922] [c000007f24ccf910] [c00000000096d910] vfio_pci_set_irqs_ioctl+0xa0/0x170 [ 1007.360941] [c000007f24ccf930] [c00000000096b400] vfio_pci_disable+0x80/0x5e0 [ 1007.360963] [c000007f24ccfa10] [c00000000096b9bc] vfio_pci_release+0x5c/0x90 [ 1007.360991] [c000007f24ccfa40] [c000000000963a9c] vfio_device_fops_release+0x3c/0x70 [ 1007.361012] [c000007f24ccfa70] [c0000000003b5668] __fput+0xc8/0x2b0 [ 1007.361040] [c000007f24ccfac0] [c0000000001409b0] task_work_run+0x140/0x1b0 [ 1007.361059] [c000007f24ccfb20] [c000000000118f8c] do_exit+0x3ac/0xd00 [ 1007.361076] [c000007f24ccfc00] [c0000000001199b0] do_group_exit+0x60/0x100 [ 1007.361094] [c000007f24ccfc40] [c00000000012b514] get_signal+0x1a4/0x8f0 [ 1007.361112] [c000007f24ccfd30] [c000000000021cc8] do_notify_resume+0x1a8/0x430 [ 1007.361141] [c000007f24ccfe20] [c00000000000e444] ret_from_except_lite+0x70/0x74 [ 1007.361159] Instruction dump: [ 1007.361175] 38422c00 e9230000 712a0004 41820010 548a2036 7d442378 78840020 71290020 [ 1007.361194] 4082004c e9230010 7c892214 7c0004ac <e9240000> 0c090000 4c00012c 792a0022 Cc: stable@vger.kernel.org # v4.12+ Fixes: 5af50993850a ("KVM: PPC: Book3S HV: Native usage of the XIVE interrupt controller") Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Greg Kurz <groug@kaod.org> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-05KVM: PPC: Book3S: Protect memslots while validating user addressAlexey Kardashevskiy1-3/+3
Guest physical to user address translation uses KVM memslots and reading these requires holding the kvm->srcu lock. However recently introduced kvmppc_tce_validate() broke the rule (see the lockdep warning below). This moves srcu_read_lock(&vcpu->kvm->srcu) earlier to protect kvmppc_tce_validate() as well. ============================= WARNING: suspicious RCU usage 5.1.0-rc2-le_nv2_aikATfstn1-p1 #380 Not tainted ----------------------------- include/linux/kvm_host.h:605 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by qemu-system-ppc/8020: #0: 0000000094972fe9 (&vcpu->mutex){+.+.}, at: kvm_vcpu_ioctl+0xdc/0x850 [kvm] stack backtrace: CPU: 44 PID: 8020 Comm: qemu-system-ppc Not tainted 5.1.0-rc2-le_nv2_aikATfstn1-p1 #380 Call Trace: [c000003fece8f740] [c000000000bcc134] dump_stack+0xe8/0x164 (unreliable) [c000003fece8f790] [c000000000181be0] lockdep_rcu_suspicious+0x130/0x170 [c000003fece8f810] [c0000000000d5f50] kvmppc_tce_to_ua+0x280/0x290 [c000003fece8f870] [c00800001a7e2c78] kvmppc_tce_validate+0x80/0x1b0 [kvm] [c000003fece8f8e0] [c00800001a7e3fac] kvmppc_h_put_tce+0x94/0x3e4 [kvm] [c000003fece8f9a0] [c00800001a8baac4] kvmppc_pseries_do_hcall+0x30c/0xce0 [kvm_hv] [c000003fece8fa10] [c00800001a8bd89c] kvmppc_vcpu_run_hv+0x694/0xec0 [kvm_hv] [c000003fece8fae0] [c00800001a7d95dc] kvmppc_vcpu_run+0x34/0x48 [kvm] [c000003fece8fb00] [c00800001a7d56bc] kvm_arch_vcpu_ioctl_run+0x2f4/0x400 [kvm] [c000003fece8fb90] [c00800001a7c3618] kvm_vcpu_ioctl+0x460/0x850 [kvm] [c000003fece8fd00] [c00000000041c4f4] do_vfs_ioctl+0xe4/0x930 [c000003fece8fdb0] [c00000000041ce04] ksys_ioctl+0xc4/0x110 [c000003fece8fe00] [c00000000041ce78] sys_ioctl+0x28/0x80 [c000003fece8fe20] [c00000000000b5a4] system_call+0x5c/0x70 Fixes: 42de7b9e2167 ("KVM: PPC: Validate TCEs against preregistered memory page sizes", 2018-09-10) Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-04-05KVM: PPC: Book3S HV: Perserve PSSCR FAKE_SUSPEND bit on guest exitSuraj Jitindar Singh1-1/+3
There is a hardware bug in some POWER9 processors where a treclaim in fake suspend mode can cause an inconsistency in the XER[SO] bit across the threads of a core, the workaround being to force the core into SMT4 when doing the treclaim. The FAKE_SUSPEND bit (bit 10) in the PSSCR is used to control whether a thread is in fake suspend or real suspend. The important difference here being that thread reconfiguration is blocked in real suspend but not fake suspend mode. When we exit a guest which was in fake suspend mode, we force the core into SMT4 while we do the treclaim in kvmppc_save_tm_hv(). However on the new exit path introduced with the function kvmhv_run_single_vcpu() we restore the host PSSCR before calling kvmppc_save_tm_hv() which means that if we were in fake suspend mode we put the thread into real suspend mode when we clear the PSSCR[FAKE_SUSPEND] bit. This means that we block thread reconfiguration and the thread which is trying to get the core into SMT4 before it can do the treclaim spins forever since it itself is blocking thread reconfiguration. The result is that that core is essentially lost. This results in a trace such as: [ 93.512904] CPU: 7 PID: 13352 Comm: qemu-system-ppc Not tainted 5.0.0 #4 [ 93.512905] NIP: c000000000098a04 LR: c0000000000cc59c CTR: 0000000000000000 [ 93.512908] REGS: c000003fffd2bd70 TRAP: 0100 Not tainted (5.0.0) [ 93.512908] MSR: 9000000302883033 <SF,HV,VEC,VSX,FP,ME,IR,DR,RI,LE,TM[SE]> CR: 22222444 XER: 00000000 [ 93.512914] CFAR: c000000000098a5c IRQMASK: 3 [ 93.512915] PACATMSCRATCH: 0000000000000001 [ 93.512916] GPR00: 0000000000000001 c000003f6cc1b830 c000000001033100 0000000000000004 [ 93.512928] GPR04: 0000000000000004 0000000000000002 0000000000000004 0000000000000007 [ 93.512930] GPR08: 0000000000000000 0000000000000004 0000000000000000 0000000000000004 [ 93.512932] GPR12: c000203fff7fc000 c000003fffff9500 0000000000000000 0000000000000000 [ 93.512935] GPR16: 2000000000300375 000000000000059f 0000000000000000 0000000000000000 [ 93.512951] GPR20: 0000000000000000 0000000000080053 004000000256f41f c000003f6aa88ef0 [ 93.512953] GPR24: c000003f6aa89100 0000000000000010 0000000000000000 0000000000000000 [ 93.512956] GPR28: c000003f9e9a0800 0000000000000000 0000000000000001 c000203fff7fc000 [ 93.512959] NIP [c000000000098a04] pnv_power9_force_smt4_catch+0x1b4/0x2c0 [ 93.512960] LR [c0000000000cc59c] kvmppc_save_tm_hv+0x40/0x88 [ 93.512960] Call Trace: [ 93.512961] [c000003f6cc1b830] [0000000000080053] 0x80053 (unreliable) [ 93.512965] [c000003f6cc1b8a0] [c00800001e9cb030] kvmhv_p9_guest_entry+0x508/0x6b0 [kvm_hv] [ 93.512967] [c000003f6cc1b940] [c00800001e9cba44] kvmhv_run_single_vcpu+0x2dc/0xb90 [kvm_hv] [ 93.512968] [c000003f6cc1ba10] [c00800001e9cc948] kvmppc_vcpu_run_hv+0x650/0xb90 [kvm_hv] [ 93.512969] [c000003f6cc1bae0] [c00800001e8f620c] kvmppc_vcpu_run+0x34/0x48 [kvm] [ 93.512971] [c000003f6cc1bb00] [c00800001e8f2d4c] kvm_arch_vcpu_ioctl_run+0x2f4/0x400 [kvm] [ 93.512972] [c000003f6cc1bb90] [c00800001e8e3918] kvm_vcpu_ioctl+0x460/0x7d0 [kvm] [ 93.512974] [c000003f6cc1bd00] [c0000000003ae2c0] do_vfs_ioctl+0xe0/0x8e0 [ 93.512975] [c000003f6cc1bdb0] [c0000000003aeb24] ksys_ioctl+0x64/0xe0 [ 93.512978] [c000003f6cc1be00] [c0000000003aebc8] sys_ioctl+0x28/0x80 [ 93.512981] [c000003f6cc1be20] [c00000000000b3a4] system_call+0x5c/0x70 [ 93.512983] Instruction dump: [ 93.512986] 419dffbc e98c0000 2e8b0000 38000001 60000000 60000000 60000000 40950068 [ 93.512993] 392bffff 39400000 79290020 39290001 <7d2903a6> 60000000 60000000 7d235214 To fix this we preserve the PSSCR[FAKE_SUSPEND] bit until we call kvmppc_save_tm_hv() which will mean the core can get into SMT4 and perform the treclaim. Note kvmppc_save_tm_hv() clears the PSSCR[FAKE_SUSPEND] bit again so there is no need to explicitly do that. Fixes: 95a6432ce9038 ("KVM: PPC: Book3S HV: Streamlined guest entry/exit path on P9 for radix guests") Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-03-16Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds13-43/+138
Pull KVM updates from Paolo Bonzini: "ARM: - some cleanups - direct physical timer assignment - cache sanitization for 32-bit guests s390: - interrupt cleanup - introduction of the Guest Information Block - preparation for processor subfunctions in cpu models PPC: - bug fixes and improvements, especially related to machine checks and protection keys x86: - many, many cleanups, including removing a bunch of MMU code for unnecessary optimizations - AVIC fixes Generic: - memcg accounting" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (147 commits) kvm: vmx: fix formatting of a comment KVM: doc: Document the life cycle of a VM and its resources MAINTAINERS: Add KVM selftests to existing KVM entry Revert "KVM/MMU: Flush tlb directly in the kvm_zap_gfn_range()" KVM: PPC: Book3S: Add count cache flush parameters to kvmppc_get_cpu_char() KVM: PPC: Fix compilation when KVM is not enabled KVM: Minor cleanups for kvm_main.c KVM: s390: add debug logging for cpu model subfunctions KVM: s390: implement subfunction processor calls arm64: KVM: Fix architecturally invalid reset value for FPEXC32_EL2 KVM: arm/arm64: Remove unused timer variable KVM: PPC: Book3S: Improve KVM reference counting KVM: PPC: Book3S HV: Fix build failure without IOMMU support Revert "KVM: Eliminate extra function calls in kvm_get_dirty_log_protect()" x86: kvmguest: use TSC clocksource if invariant TSC is exposed KVM: Never start grow vCPU halt_poll_ns from value below halt_poll_ns_grow_start KVM: Expose the initial start value in grow_halt_poll_ns() as a module parameter KVM: grow_halt_poll_ns() should never shrink vCPU halt_poll_ns KVM: x86/mmu: Consolidate kvm_mmu_zap_all() and kvm_mmu_zap_mmio_sptes() KVM: x86/mmu: WARN if zapping a MMIO spte results in zapping children ...
2019-03-02Merge branch 'topic/ppc-kvm' into nextMichael Ellerman1-9/+17
Merge another commit in the topic/ppc-kvm branch we're sharing with kvm-ppc.
2019-03-01KVM: PPC: Book3S: Add count cache flush parameters to kvmppc_get_cpu_char()Suraj Jitindar Singh1-4/+14
Add KVM_PPC_CPU_CHAR_BCCTR_FLUSH_ASSIST & KVM_PPC_CPU_BEHAV_FLUSH_COUNT_CACHE to the characteristics returned from the H_GET_CPU_CHARACTERISTICS H-CALL, as queried from either the hypervisor or the device tree. Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-02-23powerpc: Avoid circular header inclusion in mmu-hash.hChristophe Leroy1-0/+1
When activating CONFIG_THREAD_INFO_IN_TASK, linux/sched.h includes asm/current.h. This generates a circular dependency. To avoid that, asm/processor.h shall not be included in mmu-hash.h. In order to do that, this patch moves into a new header called asm/task_size_64/32.h all the TASK_SIZE related constants, which can then be included in mmu-hash.h directly. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Split out all the TASK_SIZE constants not just 64-bit ones] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-22Merge tag 'kvm-ppc-next-5.1-1' of ↵Paolo Bonzini15-133/+180
git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into kvm-next PPC KVM update for 5.1 There are no major new features this time, just a collection of bug fixes and improvements in various areas, including machine check handling and context switching of protection-key-related registers.
2019-02-22Merge remote-tracking branch 'remotes/powerpc/topic/ppc-kvm' into kvm-ppc-nextPaul Mackerras4-94/+62
This merges in the "ppc-kvm" topic branch of the powerpc tree to get a series of commits that touch both general arch/powerpc code and KVM code. These commits will be merged both via the KVM tree and the powerpc tree. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-02-22powerpc/kvm: Save and restore host AMR/IAMR/UAMORMichael Ellerman1-9/+17
When the hash MMU is active the AMR, IAMR and UAMOR are used for pkeys. The AMR is directly writable by user space, and the UAMOR masks those writes, meaning both registers are effectively user register state. The IAMR is used to create an execute only key. Also we must maintain the value of at least the AMR when running in process context, so that any memory accesses done by the kernel on behalf of the process are correctly controlled by the AMR. Although we are correctly switching all registers when going into a guest, on returning to the host we just write 0 into all regs, except on Power9 where we restore the IAMR correctly. This could be observed by a user process if it writes the AMR, then runs a guest and we then return immediately to it without rescheduling. Because we have written 0 to the AMR that would have the effect of granting read/write permission to pages that the process was trying to protect. In addition, when using the Radix MMU, the AMR can prevent inadvertent kernel access to userspace data, writing 0 to the AMR disables that protection. So save and restore AMR, IAMR and UAMOR. Fixes: cf43d3b26452 ("powerpc: Enable pkey subsystem") Cc: stable@vger.kernel.org # v4.16+ Signed-off-by: Russell Currey <ruscur@russell.cc> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Acked-by: Paul Mackerras <paulus@ozlabs.org>
2019-02-22KVM: PPC: Book3S: Improve KVM reference countingAlexey Kardashevskiy1-3/+4
The anon fd's ops releases the KVM reference in the release hook. However we reference the KVM object after we create the fd so there is small window when the release function can be called and dereferenced the KVM object which potentially may free it. It is not a problem at the moment as the file is created and KVM is referenced under the KVM lock and the release function obtains the same lock before dereferencing the KVM (although the lock is not held when calling kvm_put_kvm()) but it is potentially fragile against future changes. This references the KVM object before creating a file. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-02-22KVM: PPC: Book3S HV: Fix build failure without IOMMU supportJordan Niethe2-0/+12
Currently trying to build without IOMMU support will fail: (.text+0x1380): undefined reference to `kvmppc_h_get_tce' (.text+0x1384): undefined reference to `kvmppc_rm_h_put_tce' (.text+0x149c): undefined reference to `kvmppc_rm_h_stuff_tce' (.text+0x14a0): undefined reference to `kvmppc_rm_h_put_tce_indirect' This happens because turning off IOMMU support will prevent book3s_64_vio_hv.c from being built because it is only built when SPAPR_TCE_IOMMU is set, which depends on IOMMU support. Fix it using ifdefs for the undefined references. Fixes: 76d837a4c0f9 ("KVM: PPC: Book3S PR: Don't include SPAPR TCE code on non-pseries platforms") Signed-off-by: Jordan Niethe <jniethe5@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-02-21Merge branch 'topic/ppc-kvm' into nextMichael Ellerman4-85/+45
Merge commits we're sharing with kvm-ppc tree.
2019-02-21powerpc/64s: Better printing of machine check info for guest MCEsPaul Mackerras1-2/+2
This adds an "in_guest" parameter to machine_check_print_event_info() so that we can avoid trying to translate guest NIP values into symbolic form using the host kernel's symbol table. Reviewed-by: Aravinda Prasad <aravinda@linux.vnet.ibm.com> Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-21KVM: PPC: Book3S HV: Simplify machine check handlingPaul Mackerras4-83/+40
This makes the handling of machine check interrupts that occur inside a guest simpler and more robust, with less done in assembler code and in real mode. Now, when a machine check occurs inside a guest, we always get the machine check event struct and put a copy in the vcpu struct for the vcpu where the machine check occurred. We no longer call machine_check_queue_event() from kvmppc_realmode_mc_power7(), because on POWER8, when a vcpu is running on an offline secondary thread and we call machine_check_queue_event(), that calls irq_work_queue(), which doesn't work because the CPU is offline, but instead triggers the WARN_ON(lazy_irq_pending()) in pnv_smp_cpu_kill_self() (which fires again and again because nothing clears the condition). All that machine_check_queue_event() actually does is to cause the event to be printed to the console. For a machine check occurring in the guest, we now print the event in kvmppc_handle_exit_hv() instead. The assembly code at label machine_check_realmode now just calls C code and then continues exiting the guest. We no longer either synthesize a machine check for the guest in assembly code or return to the guest without a machine check. The code in kvmppc_handle_exit_hv() is extended to handle the case where the guest is not FWNMI-capable. In that case we now always synthesize a machine check interrupt for the guest. Previously, if the host thinks it has recovered the machine check fully, it would return to the guest without any notification that the machine check had occurred. If the machine check was caused by some action of the guest (such as creating duplicate SLB entries), it is much better to tell the guest that it has caused a problem. Therefore we now always generate a machine check interrupt for guests that are not FWNMI-capable. Reviewed-by: Aravinda Prasad <aravinda@linux.vnet.ibm.com> Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-21KVM: PPC: Book3S HV: Context switch AMR on Power9Michael Ellerman1-1/+4
kvmhv_p9_guest_entry() implements a fast-path guest entry for Power9 when guest and host are both running with the Radix MMU. Currently in that path we don't save the host AMR (Authority Mask Register) value, and we always restore 0 on return to the host. That is OK at the moment because the AMR is not used for storage keys with the Radix MMU. However we plan to start using the AMR on Radix to prevent the kernel from reading/writing to userspace outside of copy_to/from_user(). In order to make that work we need to save/restore the AMR value. We only restore the value if it is different from the guest value, which is already in the register when we exit to the host. This should mean we rarely need to actually restore the value when running a modern Linux as a guest, because it will be using the same value as us. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Tested-by: Russell Currey <ruscur@russell.cc>
2019-02-21KVM: Never start grow vCPU halt_poll_ns from value below halt_poll_ns_grow_startNir Weiner1-3/+2
grow_halt_poll_ns() have a strange behaviour in case (vcpu->halt_poll_ns != 0) && (vcpu->halt_poll_ns < halt_poll_ns_grow_start). In this case, vcpu->halt_poll_ns will be multiplied by grow factor (halt_poll_ns_grow) which will require several grow iteration in order to reach a value bigger than halt_poll_ns_grow_start. This means that growing vcpu->halt_poll_ns from value of 0 is slower than growing it from a positive value less than halt_poll_ns_grow_start. Which is misleading and inaccurate. Fix issue by changing grow_halt_poll_ns() to set vcpu->halt_poll_ns to halt_poll_ns_grow_start in any case that (vcpu->halt_poll_ns < halt_poll_ns_grow_start). Regardless if vcpu->halt_poll_ns is 0. use READ_ONCE to get a consistent number for all cases. Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Liran Alon <liran.alon@oracle.com> Signed-off-by: Nir Weiner <nir.weiner@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-02-21KVM: Expose the initial start value in grow_halt_poll_ns() as a module parameterNir Weiner1-2/+1
The hard-coded value 10000 in grow_halt_poll_ns() stands for the initial start value when raising up vcpu->halt_poll_ns. It actually sets the first timeout to the first polling session. This value has significant effect on how tolerant we are to outliers. On the standard case, higher value is better - we will spend more time in the polling busyloop, handle events/interrupts faster and result in better performance. But on outliers it puts us in a busy loop that does nothing. Even if the shrink factor is zero, we will still waste time on the first iteration. The optimal value changes between different workloads. It depends on outliers rate and polling sessions length. As this value has significant effect on the dynamic halt-polling algorithm, it should be configurable and exposed. Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Liran Alon <liran.alon@oracle.com> Signed-off-by: Nir Weiner <nir.weiner@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-02-21KVM: grow_halt_poll_ns() should never shrink vCPU halt_poll_nsNir Weiner1-1/+4
grow_halt_poll_ns() have a strange behavior in case (halt_poll_ns_grow == 0) && (vcpu->halt_poll_ns != 0). In this case, vcpu->halt_pol_ns will be set to zero. That results in shrinking instead of growing. Fix issue by changing grow_halt_poll_ns() to not modify vcpu->halt_poll_ns in case halt_poll_ns_grow is zero Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Liran Alon <liran.alon@oracle.com> Signed-off-by: Nir Weiner <nir.weiner@oracle.com> Suggested-by: Liran Alon <liran.alon@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-02-19KVM: PPC: Book3S HV: Add KVM stat largepages_[2M/1G]Suraj Jitindar Singh2-1/+17
This adds an entry to the kvm_stats_debugfs directory which provides the number of large (2M or 1G) pages which have been used to setup the guest mappings, for radix guests. Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-02-19KVM: PPC: Release all hardware TCE tables attached to a groupAlexey Kardashevskiy1-1/+0
The SPAPR TCE KVM device references all hardware IOMMU tables assigned to some IOMMU group to ensure that in-kernel KVM acceleration of H_PUT_TCE can work. The tables are references when an IOMMU group gets registered with the VFIO KVM device by the KVM_DEV_VFIO_GROUP_ADD ioctl; KVM_DEV_VFIO_GROUP_DEL calls into the dereferencing code in kvm_spapr_tce_release_iommu_group() which walks through the list of LIOBNs, finds a matching IOMMU table and calls kref_put() when found. However that code stops after the very first successful derefencing leaving other tables referenced till the SPAPR TCE KVM device is destroyed which normally happens on guest reboot or termination so if we do hotplug and unplug in a loop, we are leaking IOMMU tables here. This removes a premature return to let kvm_spapr_tce_release_iommu_group() find and dereference all attached tables. Fixes: 121f80ba68f ("KVM: PPC: VFIO: Add in-kernel acceleration for VFIO") Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-02-19KVM: PPC: Book3S HV: Optimise mmio emulation for devices on FAST_MMIO_BUSSuraj Jitindar Singh1-0/+18
Devices on the KVM_FAST_MMIO_BUS by definition have length zero and are thus used for notification purposes rather than data transfer. For example eventfd for virtio devices. This means that when emulating mmio instructions which target devices on this bus we can immediately handle them and return without needing to load the instruction from guest memory. For now we restrict this to stores as this is the only use case at present. For a normal guest the effect is negligible, however for a nested guest we save on the order of 5us per access. Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-02-19KVM: PPC: Book3S: Allow XICS emulation to work in nested hosts using XIVEPaul Mackerras6-26/+33
Currently, the KVM code assumes that if the host kernel is using the XIVE interrupt controller (the new interrupt controller that first appeared in POWER9 systems), then the in-kernel XICS emulation will use the XIVE hardware to deliver interrupts to the guest. However, this only works when the host is running in hypervisor mode and has full access to all of the XIVE functionality. It doesn't work in any nested virtualization scenario, either with PR KVM or nested-HV KVM, because the XICS-on-XIVE code calls directly into the native-XIVE routines, which are not initialized and cannot function correctly because they use OPAL calls, and OPAL is not available in a guest. This means that using the in-kernel XICS emulation in a nested hypervisor that is using XIVE as its interrupt controller will cause a (nested) host kernel crash. To fix this, we change most of the places where the current code calls xive_enabled() to select between the XICS-on-XIVE emulation and the plain XICS emulation to call a new function, xics_on_xive(), which returns false in a guest. However, there is a further twist. The plain XICS emulation has some functions which are used in real mode and access the underlying XICS controller (the interrupt controller of the host) directly. In the case of a nested hypervisor, this means doing XICS hypercalls directly. When the nested host is using XIVE as its interrupt controller, these hypercalls will fail. Therefore this also adds checks in the places where the XICS emulation wants to access the underlying interrupt controller directly, and if that is XIVE, makes the code use the virtual mode fallback paths, which call generic kernel infrastructure rather than doing direct XICS access. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Reviewed-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-02-19KVM: PPC: Remove -I. header search pathsMasahiro Yamada1-5/+0
The header search path -I. in kernel Makefiles is very suspicious; it allows the compiler to search for headers in the top of $(srctree), where obviously no header file exists. Commit 46f43c6ee022 ("KVM: powerpc: convert marker probes to event trace") first added these options, but they are completely useless. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-02-19KVM: PPC: Book3S HV: Replace kmalloc_node+memset with kzalloc_nodewangbo1-3/+1
Replace kmalloc_node and memset with kzalloc_node Signed-off-by: wangbo <wang.bo116@zte.com.cn> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-02-19KVM: PPC: Book3S PR: Add emulation for slbfee. instructionPaul Mackerras3-0/+33
Recent kernels, since commit e15a4fea4dee ("powerpc/64s/hash: Add some SLB debugging tests", 2018-10-03) use the slbfee. instruction, which PR KVM currently does not have code to emulate. Consequently recent kernels fail to boot under PR KVM. This adds emulation of slbfee., enabling these kernels to boot successfully. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-01-14KVM: powerpc: remove -I. header search pathsMasahiro Yamada1-5/+0
The header search path -I. in kernel Makefiles is very suspicious; it allows the compiler to search for headers in the top of $(srctree), where obviously no header file exists. Commit 46f43c6ee022 ("KVM: powerpc: convert marker probes to event trace") first added these options, but they are completely useless. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-01-04Merge branch 'master' into fixesMichael Ellerman2-3/+3
We have a fix to apply on top of commit 96d4f267e40f ("Remove 'type' argument from access_ok() function"), so merge master to get it.
2019-01-04Remove 'type' argument from access_ok() functionLinus Torvalds1-2/+2
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument of the user address range verification function since we got rid of the old racy i386-only code to walk page tables by hand. It existed because the original 80386 would not honor the write protect bit when in kernel mode, so you had to do COW by hand before doing any user access. But we haven't supported that in a long time, and these days the 'type' argument is a purely historical artifact. A discussion about extending 'user_access_begin()' to do the range checking resulted this patch, because there is no way we're going to move the old VERIFY_xyz interface to that model. And it's best done at the end of the merge window when I've done most of my merges, so let's just get this done once and for all. This patch was mostly done with a sed-script, with manual fix-ups for the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form. There were a couple of notable cases: - csky still had the old "verify_area()" name as an alias. - the iter_iov code had magical hardcoded knowledge of the actual values of VERIFY_{READ,WRITE} (not that they mattered, since nothing really used it) - microblaze used the type argument for a debug printout but other than those oddities this should be a total no-op patch. I tried to fix up all architectures, did fairly extensive grepping for access_ok() uses, and the changes are trivial, but I may have missed something. Any missed conversion should be trivially fixable, though. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-30KVM: PPC: Book3S HV: radix: Fix uninitialized var build errorMichael Ellerman1-1/+1
Old GCCs (4.6.3 at least), aren't able to follow the logic in __kvmhv_copy_tofrom_guest_radix() and warn that old_pid is used uninitialized: arch/powerpc/kvm/book3s_64_mmu_radix.c:75:3: error: 'old_pid' may be used uninitialized in this function The logic is OK, we only use old_pid if quadrant == 1, and in that case it has definitely be initialised, eg: if (quadrant == 1) { old_pid = mfspr(SPRN_PID); ... if (quadrant == 1 && pid != old_pid) mtspr(SPRN_PID, old_pid); Annotate it to fix the error. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-30Merge tag 'kconfig-v4.21' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kconfig updates from Masahiro Yamada: - support -y option for merge_config.sh to avoid downgrading =y to =m - remove S_OTHER symbol type, and touch include/config/*.h files correctly - fix file name and line number in lexer warnings - fix memory leak when EOF is encountered in quotation - resolve all shift/reduce conflicts of the parser - warn no new line at end of file - make 'source' statement more strict to take only string literal - rewrite the lexer and remove the keyword lookup table - convert to SPDX License Identifier - compile C files independently instead of including them from zconf.y - fix various warnings of gconfig - misc cleanups * tag 'kconfig-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (39 commits) kconfig: surround dbg_sym_flags with #ifdef DEBUG to fix gconf warning kconfig: split images.c out of qconf.cc/gconf.c to fix gconf warnings kconfig: add static qualifiers to fix gconf warnings kconfig: split the lexer out of zconf.y kconfig: split some C files out of zconf.y kconfig: convert to SPDX License Identifier kconfig: remove keyword lookup table entirely kconfig: update current_pos in the second lexer kconfig: switch to ASSIGN_VAL state in the second lexer kconfig: stop associating kconf_id with yylval kconfig: refactor end token rules kconfig: stop supporting '.' and '/' in unquoted words treewide: surround Kconfig file paths with double quotes microblaze: surround string default in Kconfig with double quotes kconfig: use T_WORD instead of T_VARIABLE for variables kconfig: use specific tokens instead of T_ASSIGN for assignments kconfig: refactor scanning and parsing "option" properties kconfig: use distinct tokens for type and default properties kconfig: remove redundant token defines kconfig: rename depends_list to comment_option_list ...
2018-12-27Merge tag 'powerpc-4.21-1' of ↵Linus Torvalds4-9/+22
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Notable changes: - Mitigations for Spectre v2 on some Freescale (NXP) CPUs. - A large series adding support for pass-through of Nvidia V100 GPUs to guests on Power9. - Another large series to enable hardware assistance for TLB table walk on MPC8xx CPUs. - Some preparatory changes to our DMA code, to make way for further cleanups from Christoph. - Several fixes for our Transactional Memory handling discovered by fuzzing the signal return path. - Support for generating our system call table(s) from a text file like other architectures. - A fix to our page fault handler so that instead of generating a WARN_ON_ONCE, user accesses of kernel addresses instead print a ratelimited and appropriately scary warning. - A cosmetic change to make our unhandled page fault messages more similar to other arches and also more compact and informative. - Freescale updates from Scott: "Highlights include elimination of legacy clock bindings use from dts files, an 83xx watchdog handler, fixes to old dts interrupt errors, and some minor cleanup." And many clean-ups, reworks and minor fixes etc. Thanks to: Alexandre Belloni, Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V, Arnd Bergmann, Benjamin Herrenschmidt, Breno Leitao, Christian Lamparter, Christophe Leroy, Christoph Hellwig, Daniel Axtens, Darren Stevens, David Gibson, Diana Craciun, Dmitry V. Levin, Firoz Khan, Geert Uytterhoeven, Greg Kurz, Gustavo Romero, Hari Bathini, Joel Stanley, Kees Cook, Madhavan Srinivasan, Mahesh Salgaonkar, Markus Elfring, Mathieu Malaterre, Michal Suchánek, Naveen N. Rao, Nick Desaulniers, Oliver O'Halloran, Paul Mackerras, Ram Pai, Ravi Bangoria, Rob Herring, Russell Currey, Sabyasachi Gupta, Sam Bobroff, Satheesh Rajendran, Scott Wood, Segher Boessenkool, Stephen Rothwell, Tang Yuantian, Thiago Jung Bauermann, Yangtao Li, Yuantian Tang, Yue Haibing" * tag 'powerpc-4.21-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (201 commits) Revert "powerpc/fsl_pci: simplify fsl_pci_dma_set_mask" powerpc/zImage: Also check for stdout-path powerpc: Fix HMIs on big-endian with CONFIG_RELOCATABLE=y macintosh: Use of_node_name_{eq, prefix} for node name comparisons ide: Use of_node_name_eq for node name comparisons powerpc: Use of_node_name_eq for node name comparisons powerpc/pseries/pmem: Convert to %pOFn instead of device_node.name powerpc/mm: Remove very old comment in hash-4k.h powerpc/pseries: Fix node leak in update_lmb_associativity_index() powerpc/configs/85xx: Enable CONFIG_DEBUG_KERNEL powerpc/dts/fsl: Fix dtc-flagged interrupt errors clk: qoriq: add more compatibles strings powerpc/fsl: Use new clockgen binding powerpc/83xx: handle machine check caused by watchdog timer powerpc/fsl-rio: fix spelling mistake "reserverd" -> "reserved" powerpc/fsl_pci: simplify fsl_pci_dma_set_mask arch/powerpc/fsl_rmu: Use dma_zalloc_coherent vfio_pci: Add NVIDIA GV100GL [Tesla V100 SXM2] subdriver vfio_pci: Allow regions to add own capabilities vfio_pci: Allow mapping extra regions ...
2018-12-21treewide: surround Kconfig file paths with double quotesMasahiro Yamada1-1/+1
The Kconfig lexer supports special characters such as '.' and '/' in the parameter context. In my understanding, the reason is just to support bare file paths in the source statement. I do not see a good reason to complicate Kconfig for the room of ambiguity. The majority of code already surrounds file paths with double quotes, and it makes sense since file paths are constant string literals. Make it treewide consistent now. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Ingo Molnar <mingo@kernel.org>
2018-12-21Merge tag 'kvm-ppc-next-4.21-2' of ↵Paolo Bonzini2-12/+88
git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into kvm-next Second PPC KVM update for 4.21 This has 5 commits that fix page dirty tracking when running nested HV KVM guests, from Suraj Jitindar Singh.
2018-12-21KVM: Make kvm_set_spte_hva() return intLan Tianyu2-2/+4
The patch is to make kvm_set_spte_hva() return int and caller can check return value to determine flush tlb or not. Signed-off-by: Lan Tianyu <Tianyu.Lan@microsoft.com> Acked-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-21powerpc/vfio/iommu/kvm: Do not pin device memoryAlexey Kardashevskiy1-8/+10
This new memory does not have page structs as it is not plugged to the host so gup() will fail anyway. This adds 2 helpers: - mm_iommu_newdev() to preregister the "memory device" memory so the rest of API can still be used; - mm_iommu_is_devmem() to know if the physical address is one of thise new regions which we must avoid unpinning of. This adds @mm to tce_page_is_contained() and iommu_tce_xchg() to test if the memory is device memory to avoid pfn_to_page(). This adds a check for device memory in mm_iommu_ua_mark_dirty_rm() which does delayed pages dirtying. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-21KVM: PPC: Book3S HV: Keep rc bits in shadow pgtable in sync with hostSuraj Jitindar Singh1-4/+18
The rc bits contained in ptes are used to track whether a page has been accessed and whether it is dirty. The accessed bit is used to age a page and the dirty bit to track whether a page is dirty or not. Now that we support nested guests there are three ptes which track the state of the same page: - The partition-scoped page table in the L1 guest, mapping L2->L1 address - The partition-scoped page table in the host for the L1 guest, mapping L1->L0 address - The shadow partition-scoped page table for the nested guest in the host, mapping L2->L0 address The idea is to attempt to keep the rc state of these three ptes in sync, both when setting and when clearing rc bits. When setting the bits we achieve consistency by: - Initially setting the bits in the shadow page table as the 'and' of the other two. - When updating in software the rc bits in the shadow page table we ensure the state is consistent with the other two locations first, and update these before reflecting the change into the shadow page table. i.e. only set the bits in the L2->L0 pte if also set in both the L2->L1 and the L1->L0 pte. When clearing the bits we achieve consistency by: - The rc bits in the shadow page table are only cleared when discarding a pte, and we don't need to record this as if either bit is set then it must also be set in the pte mapping L1->L0. - When L1 clears an rc bit in the L2->L1 mapping it __should__ issue a tlbie instruction - This means we will discard the pte from the shadow page table meaning the mapping will have to be setup again. - When setup the pte again in the shadow page table we will ensure consistency with the L2->L1 pte. - When the host clears an rc bit in the L1->L0 mapping we need to also clear the bit in any ptes in the shadow page table which map the same gfn so we will be notified if a nested guest accesses the page. This case is what this patch specifically concerns. - We can search the nest_rmap list for that given gfn and clear the same bit from all corresponding ptes in shadow page tables. - If a nested guest causes either of the rc bits to be set by software in future then we will update the L1->L0 pte and maintain consistency. With the process outlined above we aim to maintain consistency of the 3 pte locations where we track rc for a given guest page. Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-12-21KVM: PPC: Book3S HV: Introduce kvmhv_update_nest_rmap_rc_list()Suraj Jitindar Singh2-2/+53
Introduce a function kvmhv_update_nest_rmap_rc_list() which for a given nest_rmap list will traverse it, find the corresponding pte in the shadow page tables, and if it still maps the same host page update the rc bits accordingly. Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-12-21KVM: PPC: Book3S HV: Apply combination of host and l1 pte rc for nested guestSuraj Jitindar Singh1-0/+3
The shadow page table contains ptes for translations from nested guest address to host address. Currently when creating these ptes we take the rc bits from the pte for the L1 guest address to host address translation. This is incorrect as we must also factor in the rc bits from the pte for the nested guest address to L1 guest address translation (as contained in the L1 guest partition table for the nested guest). By not calculating these bits correctly L1 may not have been correctly notified when it needed to update its rc bits in the partition table it maintains for its nested guest. Modify the code so that the rc bits in the resultant pte for the L2->L0 translation are the 'and' of the rc bits in the L2->L1 pte and the L1->L0 pte, also accounting for whether this was a write access when setting the dirty bit. Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-12-21KVM: PPC: Book3S HV: Align gfn to L1 page size when inserting nest-rmap entrySuraj Jitindar Singh1-0/+2
Nested rmap entries are used to store the translation from L1 gpa to L2 gpa when entries are inserted into the shadow (nested) page tables. This rmap list is located by indexing the rmap array in the memslot by L1 gfn. When we come to search for these entries we only know the L1 page size (which could be PAGE_SIZE, 2M or a 1G page) and so can only select a gfn aligned to that size. This means that when we insert the entry, so we can find it later, we need to align the gfn we use to select the rmap list in which to insert the entry to L1 page size as well. By not doing this we were missing nested rmap entries when modifying L1 ptes which were for a page also passed through to an L2 guest. Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-12-21KVM: PPC: Book3S HV: Hold kvm->mmu_lock across updating nested pte rc bitsSuraj Jitindar Singh1-6/+12
We already hold the kvm->mmu_lock spin lock across updating the rc bits in the pte for the L1 guest. Continue to hold the lock across updating the rc bits in the pte for the nested guest as well to prevent invalidations from occurring. Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-12-20Merge tag 'kvm-ppc-next-4.21-1' of ↵Radim Krčmář11-60/+368
git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc PPC KVM update for 4.21 from Paul Mackerras The main new feature this time is support in HV nested KVM for passing a device that is emulated by a level 0 hypervisor and presented to level 1 as a PCI device through to a level 2 guest using VFIO. Apart from that there are improvements for migration of radix guests under HV KVM and some other fixes and cleanups.
2018-12-20powerpc/fsl: Flush branch predictor when entering KVMDiana Craciun1-0/+4
Switching from the guest to host is another place where the speculative accesses can be exploited. Flush the branch predictor when entering KVM. Signed-off-by: Diana Craciun <diana.craciun@nxp.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>